The present invention relates to a new and improved construction of apparatus for driving the rolling cradle of a gear-cutting machine of the type comprising a variable-speed motor for changing the generating speed.
In the case of gear-cutting machines it is already known to the art to change the rotational speed of the tool as a function of the cutter diameter or as a function of the work-piece diameter if there are produced bevel gears according to the Palloid technique with cone-shaped tools.
Further, it is known during grinding of gears to alter the generating speed as a function of the grinding stroke in the lengthwise direction of the gear teeth.
With these known apparatuses it is however not possible to accommodate the generating speed to the optimum cutting capacity or efficiency. At the beginning of the generating operation, with constant generating speed, the cutting capacity is considerably greater than at the end of the rolling operation. If the generating speed remains constant during the entire manufacturing operation, then the cutting efficiency either is too great at the start or too small at the end.